1. Field of the Invention
The present invention relates to an insertion assisting tool for an endoscope, and particularly, relates to an insertion assisting tool of an endoscope which is used when an insertion section of the endoscope is inserted into a body cavity.
2. Description of the Related Art
When the insertion section of an endoscope is inserted into a deep alimentary canal such as a small intestine, by only pushing the insertion section into the deep alimentary canal, the force is difficult to transmit to a tip end of the insertion section due to complicated bending of an intestinal canal, and insertion into a deep part is difficult. Namely, if excessive bending and deflection occur to the insertion section, it is difficult to insert the insertion section further into a deeper part. Thus, there is proposed an endoscope apparatus which prevents excessive bending and deflection of the insertion section by inserting the insertion section into a body cavity with an insertion assisting tool called an over tube or a sliding tube attached to the insertion section of the endoscope, and inserting the insertion section into the body cavity while guiding the insertion section with this insertion assisting tool (for example, Japanese Patent Application Publication No. 10-248794).
Meanwhile, a double balloon type endoscope apparatus disclosed in Japanese Patent Application Publication No. 2002-301019 includes an endoscope with an inflatable and deflatable balloon attached to a tip end peripheral portion of an endoscope insertion section, and an over tube which serves as a guide at the time of insertion of the insertion section, with an inflatable and deflatable balloon attached to the tip end peripheral portion, and the endoscope insertion section inserted into the over tube. This double balloon type endoscope apparatus is for inserting the endoscope insertion section into a deep part of an alimentary canal by carrying out an insertion operation of the over tube and the endoscope insertion section and the inflation and deflation operations of the two balloons in accordance with a predetermined procedure.